The December 2006 issue of MIT's journal Technology Review offers this article from economics writer James Surowiecki: Philanthropy's New Prototype // Will the [$100 laptop] Save the World? It's an interesting look at the economics of the $100 laptop (which is more likely to cost $150, at least initially).
Surowiecki writes "Negroponte [cofounder of MIT's Media Lab, Nicholas Negroponte] has said that the $100 laptop will not go into production until he has firm commitments from governments to buy at least five million units." Yipes! The One Laptop per Child (OLPC) group, hopes to get 5 countries to commit to one million each; so far only Libya has signed a contract for one million units.
One unexpected component to the article is that it opens with a one-page history of the Carnegie libraries. Surowiecki talks about the cost to launch a public library and compares the OLPC project to Carnegie's project over 100 years ago.
(see also part 2 and part 3 of the article)